Crimping mechanism



Jan. 21, 1958 G. MARIAN! ETAL CRIMPING MECHANISM '2 Sheets-Sheet 1 Filed Oct. 24, 1952 INVENTORS GIUSEPPE MARIANI LUIGI NOTARBARTOLO WERNER MUENCH ATTORNEYS Jan. 21, 1958 e. MARIANI ETAL CRIMPING MECHANISM Filed Oct. 24, 1952 2 Sheets-Sheet 2 INVENTORS GIUSEPPE I MARIANI LUIGI NOTARBA LO WERNER MUEN Unite 14 Claims. (Cl; .28-1) This. invention relates to. a device for the crimping of filaments, bundles'of filaments or slivers of textile fibres, inparticular artificial and synthetic fibres.

It is known that in. principle textile fibres may be crimped by subjecting amass of fibres, that may be in the formv of continuous filamentsor filament bundles, to pressure in a. suitable chamber, and that such pressure may be continuously generated by forcing: on the one hand the fibres or filaments into said chamber while on the other hand opposing their egress. therefrom. Several devices have been proposedtocarry. intopractice in different ways the aforesaid general principle, butnone of them has proved; completely satisfactory for continuous industrial operation. The device according to this invention, on the contrary, effects an efficient crimping, is regular'and'relia'ble in operation, and employs extremely siinplemeans.

Thei'nvention' maybe better understood with reference to the appended drawings wherein Fig. 1 diagrammaticall'y represents a device embodying'the invention,..seen in one operatingsta-ge; Fig; 2" represents inthe same manner the" samedevice in a d'iiferent operating stage; Fig. 3 illustratesmore completely, but always rather schematiically, a particular embodiment of t-he'i'nvention; Figures '4 and 5"simil'arly' il'l ustrateother embodiments; and a further embodiment is partially shown in perspective in Fig. 6, while one half of the same is shown more completely in lateral and sectional viewin' Fig. 7. Figs. '8a-and 8'b show in perspective view two modifications of certain elements of the. device according to the invention, and

precisely of the subsidiary rollers.

In. all. the figures. the device is showrr'as substantially comprising a pair of -rollers,indicated. inall thedrawings bynumerals. 1d-1llfl for propelling the fibreinrthe shape of continuous filaments, or filament bundles or in. any:

other form, which shall be generally designated; as yarn-J anda second pair of rollers,.indicated1in' allathe drawings'by numerals 1111, mounted in such. a way as to. oppose the. travel.- of the yarn and. create. the resist ance thereto required to produce crimping. Preferably,

as indicated in the. drawings, rollers 1111 are considerably smaller in diameter than propelling rollers:

10'.. Itis obvious that four rollers when. they contact each other or come very near to contacting. each other, define aspace having. a curvilinear four-sided section, indicated in all the drawings by numerals 12, andv which maybe called crimping chamber.

Propelling rollers 10-10, one of which at least is keyed to a driving shaft While the. other may be similarly driven or'free, may have the-same or diiferentdiametersand may have. a smooth or a rough, knurled, grooved or in ,any way uneven surface; they may conveniently be assembled in such a way as to exert a suitable, ifdesired controllable, pressure on one another in order to accomtates PatentQ 2,320,278 Patented Jan. 21, 19.58

trolled for instance by suitable screws, as is schematically illustrated in Fig. 7. Subsidiary rollers 1111 that will be called friction rollers for reason-s that will better appear hereinafter, in a preferred embodiment are mounted so as to be capable of undergoing concurrent displacements along two component directions constantly perpendicular to one another, and precisely each friction roller (or better its axis) may undergo relatively ample displacements along circular arcs concentric with the surface of the adjacent propellingrol-ler-and generally small displacementsin thedirection of the line that connects the centers of said. friction roller and of theadjacent propellingroller. Any assemblage that will allow the friction roller to undergo an aggregate displacement that can be geometrically decomposed intotwo component displacements ofthe types: aforesaid, evenif said aggregate.

towards pivot. 15.. and. thustends to maintain the contact between the peripheries of rollerslll and 11.

Any suitable means are further provided elastically to urge. rollers 11 and 11 towards. one another, and... said means may be suitably attached springs, for instance,

1717 of Fig.3 which act on theends of arms 141'47,. or springs 18-18" of Fig. 4 which actperpendicularly; to'arms14-14"in the direction of'sha'fts 1313,, or the... single spring 1'9 of Fig. 5 which recalls the ends of'arms' 1'4-14 towards one another, or finally spring 36' (and; the corresponding symmetric spring) of Fig. 6. "Of' course, roller 1'I"ismounted in a manner'perfectlyanalbgous to that of roller 11. The inactive position ofthe device, and therefore theposition it has when it startsto' operate, is'that schematized in Fig; 1, wherein all elastic -means are in a=condition of minimum deformation.

At thebeginning ofthe-operation, when the propelling ro'llers are driven into rotation, the friction rollers, thatare free on their shafts, may rotate in turn by effect oft their frictional contact with thepropelling rollers, in the" Concurrently;

direction of the arrows marked in Fig. 1. the band, bundle of filaments or sliver 20 penetrates: into thecrimping chamber 12 and, since it cannot'leavev it, iti' As the" yarn accumulates in the crimping chamber, a pressureis;

fills the same assuming a zig-zag configuration.

createdtherein whichvcauseswit tobecomecrimped.

This pressure also generates a friction between yarnsand rollers. 1111 that opposes the rotation of said rollers in the direction of the arrowsof Fig. 1, and indeed tends to cause the rollers to rotate in theopposite direction. Artfirst', therefore, there is. contrast between the friction of the propelling rollers and the friction of theyarnon. rollers. 1111, therelative intensity of'said: frictions depending of course onthe specific: characteristics .of the device and amongothers, on the. graduation of the,

1 springs.

modate possible differences, for instance differences in In. the end the: friction of the-yarn always prevails, also. because the pressure of the yarntends" to move. rollers 1111 away not only from one another but fromthe It may be that rollers 1111-E. never cease to contact the propelling rollers, inasmuch; as it. sufiicesthat the pressure of the first mentioned on; the second mentioned rollers be brought down to zero.--; or at least so lightened as to assure that the friction oft: the yarn should overcome the friction: of the propelling:

propelling rollers, as well.

rollers thus. stopping the rotation of rollers 1111".

With reference in the first place to the embodiment illustrated in Figs. 3 and 4, the pressure of the yarn tends to move rollers 11-11 away from one another overcoming the resistance of springs 17-17 or 18-18 or of the equivalent means that may be provided, and at the same time tends to move each friction roller away from the contacting propelling roller, overcoming the resistance of springs 16-16 or of the analogous means provided for the same purpose. This happens because the resultant of the forces exerted by sliver 20 on each friction roller has a component perpendicular to line 13-15 or respectively 13'-15 and a component parallel to' the direction of travel of the yarn viz. perpendicular to line 13-13. The device assumes then the configuration of Fig. 2; the two friction rollers move away from one another allowing the crimped yarn to issue from chamber 12. In this position, rollers 11-11 do not rotate to any significant degree as long as the yarn discharges easily from the crimping chamber, but if said yarn accumulates therein and the pressure rises then rollers 11-11' intermittently rotate in the direction of the arrow of Fig. 2 facilitating the discharge of the yarn and the release of the pressure generated within that chamber. This occurs because under such conditions the friction of the yarn n rollers 11-11' is the dominating factor.

If the pressure of the yarn within chamber 12 decreases, rollers 11-11' drawn nearer to each other thereby causing said pressure to increase, and said increase forces said roller to move again away, and thus the pressure oscillations that may occur are automatically compensated and the crimped yarn issues from chamber 12, possibly at a variable rate.

It may also be convenient to drive the friction rollers only when they have reached a certain distance from the propelling rollers and from one another, for instance by means of a device such as that illustrated in Fig. 5. There, two driven rollers 21-21 are provided in a fixed position, and said rollers in the initial operating stage rotate without performing any work. As rollers 11-11' draw away from each other, they get nearer to rollers 21-21 as it is seen in Fig. 5. Therefore, if for any reason yarn 20 should not be discharged from chamber 12 with the proper speed, it would accumulate therein pushing rollers 11-11' constantly farther away from each other until said rollers would bear against the rollers 21-21 and be driven thereby into rotation, thereby facilitating the discharge of the yarn from chamber 12. Rollers 21-21 could also be located internally of rollers 11-11' by making these latter hollow.

Friction rollers 11-11' may have a smooth surface but they also may conveniently be ribbed, knurled, toothed or have a surface roughened or made uneven in any suitable manner to facilitate the generation of friction between them and the yarn, as indicated with respect to roller 11 in Fig. 5. They may have the same diameter or different diameters as in Fig. 5, taking also into account the possibility that the propelling rollers may have different diameters.

A particularly advantageous manner to drive the friction rollers is shown by way of example in Figs. 6 and 7.

Numerals 15-15' again indicate the shafts of the main rollers. A sleeve 22 (Fig. 7) is free on shaft 15. An arm 23 is rigidly connected to said sleeve and is also rigidly connected to sleeve 24 concentrically whereof a pivot 25 may freely turn. On said pivot 25 there is also pivoted a' sleeve 26 and normally the sleeve 26 would be obscured by the sleeve 24 in Fig. 7. However, it will be seen that in this figure, the sleeve 24 has been broken away to show the sleeve 26. A rod 27 is rigidly connected to sleeve 26 and to said rod there is rigidly connected sleeve 28 concentrically whereof there may freely rotate the shaft, designated therein by numeral 30, of subsidiary roller 11 which latter is located behind a plate 29 illustrated in part, said plate serving to make a tight con tact with the end faces of the four rollers and to close, in cooperation with another symmetric plate, the crimping device in the direction of the axes of the rollers. Analogous or equivalent tight closure means should of course be understood as being provided in all the embodiments of the invention. The word tight of course refers to the capacity to retain the yarn. To sleeves 28 there is also connected an arm 31 and to this latter a rod 32 which passes with a small clearance through a bore or a bracket 33 rigidly connected to sleeve 22. A spring 34 located between nut 35 and bracket 33 tends to press friction roller 11 against main roller 10. In fact it is seen that, by virtue of the connections indicated hereinmanually to set each time the position of shaft 30 with respect to shaft 15 causing by other suitable means rod 32 and bracket 33 to have a threaded engagement. Finally, shaft 30 is urged towards shaft 30' of the other subsidiary roller 11, by spring 36 which acts through rod 37 on arm 38 rigidly fixed to sleeve 28. The combination of parts described up to this point, which constitutes one particular way to bring into being the relative mobility of the roller, already shown as brought about in another way according to Figs. 3 to 5, is symmetrically repeated on the right side in correspondence to rollers 10' and 11. The only parts illustrated in Fig. 7 which are not generally repeated on the right side are the spring 51 with its housing and the set screw 52 which serve elastically to urge main roller 10 against the right hand roller 10. The shafts 15-15' of the main roller carry eccentrics 40-40 whereon are freely mounted sleeves 41-41 provided with arms 42-42 to which there are pivoted at 43-43 the small cylinders 44-44'. Ratchet wheels 45-45 having suitably shaped teeth substantially as indicated in the drawings are keyed to shafts 30-30. Stop pawls 46-46, pivoted in any suitable way on any fixed portion of the device and provided with return springs not illustrated, prevent the rotation of wheels 45-45 and therefore of the friction rollers in a direction opposite to the rotation of the corresponding propelling rollers which occurs as indicated by the arrows. Cylinders 44-44 carry fingers 47-47 having a conveniently shaped point and which are constantly urged towards ratchet wheels 45-45 by springs 48-48 or like means, said fingers operating as actuating pawls for said ratchet wheels.

The operation of the device is evident. The rotation of propelling rollers 10-10 and the corresponding shafts produces through eccentrics 40-40 an alternating motion of cylinders 44-44 and therefore of fingers or pawls 47-47. These latter, in their stroke in one direction (downwards in Fig. 6) slide without effect on the teeth of wheels 45-45' which are held fast by stop pawls 46-46, while in their stroke in the other direction they engage such teeth and cause the ratchet wheels and therefore the friction rollers 11-11 to rotate in the same direction in which the corresponding propelling roller rotates.

Therefore the friction rollers will complete one turn while the propelling rollers complete as many turns as are the teeth of wheel 45-45'. A lost motion connection is thereby effected between main and friction rollers. It is I vention are superior to those achieved by known devices and in a certain sense surprising as well. Actually, a

fundamental difiiculty often met with in devices of this kind and which up to now has not been completely solved in spite of all efforts, consists in that it is very difiicult toassure a tight closure of a crimping chamber when the yarn is fed continuously. In particular, when propelling rollers are employed to force the yarn into the crimping chamber, it is found that the yarn itself invariably penetrates between the propelling rollers and any plate, wall, packing or other organ that may have been provided to assure the tightness at that point. At first sight it would seem that a device like that described herein should increase this difficulty because in the initial stage (Fig. 1) it seems that the motion of the friction rollers should draw the yarn between each of them and the adjacent propelling roller, while in the normal operating stage (Fig. 2) it seems that the yarn should easily penetrate in the gap that may have been created or in the low or zero pressure zone between each friction roller and the adjacent propelling roller. On the contrary, experience has proved that this does not occur and precisely that the tightness is perfect both in the initial, actually very short, stage and in the normal operating stage, and further that the travel of the yarn and its discharge from the crimping chamber acquire, with the device described, a regularity and a reliability never achieved hitherto.

Even if some filaments should infiltrate between the propelling rollers and the rollers 1111', when these latter rotate as in Fig. l orare still, the subsequent intermittent rotation of rollers lit-11 would certainly carry said filaments back into the crimping chamber.

With the device accoding to the invention one can operate at high yarn speed, for instance at one hundred meters per minute and even more. It is further understood that the device may be provided, besides the abovementioned closure means, with accessory organs, such as for instance means for leading a lubricating liquid to the yarn.

As already stated, the subsidiary rollers may have smooth, rough or irregular surfaces. Fig. 8a shows in perspective View a pair of subsidiary rollers 60-60' having grooved surfaces. Fig. 8b shows in like view another pair of subsidiary rollers 61-61' having knurled surfaces.

Many variations and modifications may of course be made by persons skilled in the art in the device as illustrated, far instance by substituting for the springs means operating to attain the same end, be they resilient, gravity or other means, by mounting and connecting in different ways the various organs of the device, by adding subsidiary organs, or in other ways, Without exceeding the scope of the invention.

What I claim is:

1. Device for crimping textile filaments, yarn, bundles of filaments and like materials, comprising two propelling rollers for propelling the filaments, two subsidiary rollers, means for mounting said subsidiary rollers with their axes substantially parallel to those of said propelling rollers and displaceable perpendicularly thereto, one of said subsidiary rollers being positioned adjacent to one of said propelling rollers and the other subsidiary roller being positioned adjacent to the other propelling roller resilient means urging said subsidiary rollers against one another and each. against the propelling roller adjacent thereto to define a crimping chamber extending longitudinally in a direction parallel to the axes of the rollers, and means for substantially sealing said crimping chamber at its two longitudinally opposed ends whereby said chamber is substantially completely closed when the device is in an inoperative position, the direction of rotation of said propelling rollers, when the device is in operation, being such that they force the filaments into said crimping chamber whereby a pressure is built up therein to cause the filaments to become crimped, said resilient means yielding to said pressure to allow the crimped filaments to be discharged from the crimping chamber.

2. Device according to claim 1 wherein the means for mounting the subsidiary rollers allow displacements of each subsidiary roller that are the geometric sum of one displacement concentric to the surface of the adjacent propelling roller and one displacement directed along the line of the centres of the axes of said subsidiary roller and said adjacent propelling roller.

3. Device according to claim 1, wherein the subsidiary rollers are so positioned with respect to the propelling rollers that the pressure of the filaments propelled by said propelling rollers has at all times a component tending to push said subsidiary rollers away from one another and another component tending to push each of said subsidiary rollers away from the adjacent propelling roller.

4. Device according to claim 1, wherein the subsidiary rollers are free on their shafts.

5. Device according to claim 1, wherein the subsidiary rollers are free on their shafts, and wherein there are provided fixed driven rollers in such a position that they are engaged by the subsidiary rollers when these latter have drawn apart from one another and from the propelling rollers to a predetermined extent, whereby the subsidiary rollers are driven in turn.

6. Device according to claim 1, wherein the forces of the resilient means are of such intensity that, as soon as a predetermined yarn pressure is generated in the crimping chamber, the friction exerted by said filaments in said yarn on the subsidiary rollers overcomes the frictional force exerted between said subsidiary rollers and the propelling rollers whereby any rotation of the subsidiary rollers in the directions that would correspond to the fricitonal action of the propelling rollers, ceases.

7. Device according to claim 1, comprising means for operatively connecting each subsidiary roller and the adjacent propelling roller for setting said subsidiary roller to rotate in the same direction as said propelling roller.

8. Device according to claim 1, comprising means for intermittently operatively connecting each subsidiary roller and the adjacent propelling roller for setting said subsidiary roller to rotate in the same direction as said propelling roller.

9. Device according to claim 1, wherein a pawl-ratchet engagement for operatively connecting each subsidiary roller and the adjacent propelling roller for setting said subsidiary roller to rotate in the same direction as said propelling roller.

10. Device according to claim 1, comprising an eccentric keyed to the shaft of each propelling roller, a ratchet wheel keyed to the shaft of the adjacent subsidiary roller, a pawl engaging said ratchet wheel, means for operatively connecting said pawl to said eccentric whereby to cause an intermittent rotation of said ratchet wheel in the direction of the rotation of said eccentric, and means for blocking any rotation of said ratchet wheel in the opposite direction.

11. Device according to claim 1, comprising subsidiary rollers having their surfaces with indentations.

12. Device according to claim 1, comprising two arms pivoted respectively at the axis of the two propelling rollers, and two supports slidable each on one of said arms, the subsidiary rollers being mounted each on one of said two supports.

13. Device according to claim 1, comprising two arms pivoted respectively at the axis of the two propelling rollers, two rods pivoted each to one of said arms, and two shafts journalled each in one of said levers, the subsidiary rollers being mounted each on one of said shafts.

14. Device according to claim 1, wherein the accumulation of yarn in the chamber causes the subsidiary rollers to rotate whenever the pressure of the yarn in the crimp ing chamber has reached a predetermined limit.

References Cited in the file of this patent UNITED STATES PATENTS 

